The present invention relates to an apparatus and method for fabrication of textiles or the like, and in particular to the use of liquid jets to false twist textile filament yarns and twist textile staple products such as yarn, sliver or roving.
It is known to apply a twist to a textile staple product to give the product satisfactory coherence by passing the product through a twisting jet in which a jet or jets of air are directed onto the traveling product offset from its axis to impart a twisting torque to the product. The diameter of a textile product is relatively small, for example jet manufacture are extremely tight if satisfactory processing is to be achieved and consistency of performance from jet to jet. Typically, a textile machine for performing such a process can have over 200 processing stations, i.e., over 200 yarns are processed simultaneously in parallel threadlines. This means that the machines are very large, which leads to problems of ergonomics. Furthermore, the provision of tight tolerance texturing jets and high pressure air to such jets is expensive and such a machine is very noisy, particularly when one or more doors of the jet boxes are open for threading purposes.
It has also been proposed to use a texturing jet to apply a false twist to a textile filament yarn. This proposed method consists of passing the yarn through a texturing jet wherein, like the twisting jet described above, a jet or jets of air are directed onto the traveling yarn offset from its axis to impart a twisting torque to the yarn. The twist levels achievable by this method are very low by comparison with those achieved by the use of friction discs, belts and the like, hence the limited use commercially. The tolerances on this type of air jet manufacture are especially tight since the diameter of a textile yarn, for example 0.2 mm for 150 Denier, is even smaller than when using an air jet to apply a twist to a textile staple product. In addition, since from a production costs point of view it is desirable to increase the yarn processing speed as much as possible, a limit on such speed is the surge speed, the speed at which satisfactory processing breaks down due to the long uncontrolled lengths of yarn in the machine.
The present invention provides a method of applying twist to a textile product comprising passing the product along a path through a device while applying a rotational force to the product with at least one jet of liquid directed by the device.
The method can also comprise applying a forwarding force to the product. The method can comprise applying at least one axially offset jet of liquid to the surface of the product. The method can comprise applying the at least one jet of liquid with components of velocity both along and laterally of the path through the jet device. The method can comprise applying a plurality of jets of liquid disposed about the path through the jet device, which jets can be symmetrically disposed. Preferably, three such jets of liquid are provided. Preferably the liquid is water and can be cold water. The method can also comprise passing the product successively through a plurality of liquid jet devices. Consecutive jet devices can apply rotational forces to the product in the same or in opposite directions.
The invention also provides a process, in which a twist is applied to the product by the above method, comprising controlling the product by a feedback arrangement. In this case, a property of the product can be measured and the measurement used to control the product processing. The measurement can be used to control the liquid jet device or the product speed.
The process can comprise cooling the product. The product can be cooled by the liquid jet device.
The invention can also comprise an apparatus for applying twist to a textile product comprising a liquid jet device adapted to apply a rotational force to a product traveling along a path through the jet device.
The liquid jet device can be adapted to apply a forwarding force to the traveling product. The jet device can apply at least one axially offset jet of liquid to the surface of the product. The at least one jet of liquid can be directed to have velocity components both along and laterally of the path through the jet device. A plurality of jets can be disposed about the path. through the jet device, preferably symmetrically. Three such jets can be provided. The liquid jet device can comprise a housing having an axial bore terminating in a product constricting outlet, the axis of the bore defining a path therethrough, with at least one liquid flow channel aimed towards the outlet and offset from the axis. The liquid jet device can comprise a casing having at least one seal against liquid escape along the path. The seal can be a labyrinth seal and can be pressurized. The seal can be gas pressurized, and can be pressurized by compressed air. Preferably the liquid jet device comprises a water jet device. A plurality of liquid jet devices can be disposed successively along the path, and the plurality of jet devices can be provided in a common casing. Three such jet devices can be so provided. Consecutive liquid jet devices can be adapted to apply rotational forces to the product in the same or in opposite directions.
The apparatus can comprise a feedback arrangement operable to control the product processing. The feedback arrangement can comprise a measuring instrument operable to measure a property of the product and produce a signal proportional to the measurement, and control means operable in response to the signal to control the product processing. The control means can be operable to control the rate or the pressure of the flow of liquid to the liquid jet device or the product speed.
The apparatus can comprise cooling apparatus, which can comprise the liquid jet device. The apparatus can also comprise winding apparatus disposed downstream of the liquid jet device.
The present invention also provides a method of applying a false twist to a textile filament yarn comprising passing the yarn along a yarn path while applying a rotational force to the yarn by a liquid jet device.
The invention also provides a process for applying twist to a filament yarn, in which the false twist is applied to the yarn by the above method and the yarn is cooled. The yarn can be cooled by the liquid jet device. The yarn can be heated prior to being cooled and twisted, and can then be wound up. The yarn can be passed through a twist trap, a heating zone, a cooling zone and the liquid jet device, being twisted by the latter so that the twist runs back to the twist trap, and then wound up. The yarn can be heated as far upstream as the twist trap. The yarn can be heated prior to passing through the twist trap and not further heated between the twist trap and the liquid jet device. The yarn can be drawn prior to being cooled and twisted.
The yarn can be cooled by immersion in a cooling liquid, in which case the cooling liquid can be moved in contraflow to the yarn passing through the cooling zone. The cooling zone and the liquid jet device can be contiguous. The cooling liquid can be the liquid of the jet device. The process can comprise heating the yarn by vapor, which can be superheated steam.
The yarn can be post-treated prior to it being wound up. In this case, the yarn can be passed with controlled overfeed through heating apparatus. The heating apparatus can comprise vapor heating, which can be superheated steam.
The invention can also comprise an apparatus for applying twist to a textile filament yarn comprising a liquid jet device adapted to apply a rotational force to a yarn traveling along a yarn path through the jet device.
The apparatus can also comprise a yarn heating apparatus, which can be upstream of the cooling apparatus. The apparatus can comprise winding apparatus disposed downstream of the liquid jet device. The apparatus can also comprise drawing means, which can be disposed upstream of the cooling apparatus. The heating apparatus, cooling apparatus and liquid jet device can be mounted in a common housing.
The yarn cooling apparatus can be a fluid cooling apparatus in which the yarn passes through a fluid to be cooled by heat transfer thereto. The yarn cooling apparatus can comprise a cooling chamber with a fluid inlet and a fluid outlet for cooling fluid to be passed therethrough, and a yarn inlet and yarn outlet. The cooling fluid can be passed contraflow relative to the yarn. The cooling chamber can comprise seals against escape of cooling fluid at the yarn inlet and the yarn outlet. The seals can be labyrinth seals and can be pressurized. The seals can be gas pressurized, and can be pressurized by compressed air. The cooling fluid can be a liquid and can be water. The flow of liquid through the cooling chamber can be arranged to be turbulent. The liquid jet device and the cooling apparatus can have a common liquid.
The heating apparatus can comprise a vapor heating apparatus. The vapor can be superheated steam. The heating apparatus can comprise a housing having seals against escape of steam at a yarn inlet and at a yarn outlet thereof The seals can be labyrinth seals and can be pressurized. The seals can be gas pressurized, and can be pressurized by compressed air or by superheated steam. The heating apparatus, the cooling apparatus and the liquid jet device can be disposed in a common housing.
The apparatus can also comprise treatment means operable to post treat the yarn. In this case, the apparatus can comprise feed means operable to pass the yarn with controlled overfeed through a further heating apparatus. The further heating apparatus can be a vapor heating apparatus. The heating apparatus and the further heating apparatus can use the same vapor in sequence.
Other features and advantages of the invention will be apparent from the following specification taken in conjunction with the following drawings.